We consider a model of international sovereign debt where repayment is enforced because defaulting nations lose their reputation and consequently, are excluded from international capital markets. Underlying the analysis of reputation is the hypothesis that borrowing countries have different, unobservable, attitudes towards the future. Some regimes are relatively myopic, while others are willing to make sacrifices to preserve their access to debt markets. Nations' preferences, while unobservable, are not fixed but evolve over time according to a Markov process. We make two main points. First we argue that in models of sovereign debt the length of the punishment interval that follows a default should be based on economic factors rather than being chosen arbitrarily. In our model, the length of the most natural punishment interval depends primarily on the preference parameters. Second, we point out that there is a more direct way for governments to regain their reputation. By offering to partially repay loans in default, a government can signal its reliability. This type of signaling can cause punishment interval equilibria to break down. We examine the historical record on lending resumption to argue that in almost all cases, some kind of partial repayment was made.

We construct a model of the product cycle featuring endogenous innovation and endogenous technology transfer. Competitive entrepreneurs in the North expend resources to bring out new products whenever expected present discounted value of future oligopoly profits exceeds current product development costs. Each Northern oligopolist continuously faces the risk that its product will be copied by a Southern imitator, at which time its profit stream will come to an end. In the South, competitive entrepreneurs may devote resources to learning the production processes that have been developed in the North. There too, costs (of reverse engineering) must be covered by a stream of operating profits. We study the determinants of the long-run rate of growth of the world economy, and the long-run rate of technological diffusion. We also provide an analysis of the effects of exogenous events and of public policy on relative wage rates in the two regions.

Across developing countries, capital market inefficiencies tend to decrease and external borrowing tends to sharply increase as national wealth rises. We construct a simple model of intertemporal trade under asymmetric information which provides a coherent explanation of both these phenomenon, without appealing to imperfect capital mobility. The model can be applied to a number of policy issues in LDC lending, including the debt overhang problem, and the impact of government guarantees of private debt to foreign creditors. In the two-country general equilibrium version of the model, an increase in wealth in the rich country can induce a decline in investment in the poor country via a "siphoning effect". Finally, we present some new empirical evidence regarding the link between LDC borrowing and per capita income.